Pneumatic tool.



PATENTED JtfrlYbfleov.

.S. OLDHAM. PNEUMATIC TOOL; APPLICATION FILED APR.21,1904.

2 SHEETSSI IBBT l.

UNITED STATES PA ENT OFFICE.

SAMUEL OLDHAM, OF PHILADELPHIA, PEN'NsYLvANrA.

PNEUMATIC TOQL.

To all. whom it may concern:

Be it known that I, SAMUEL OLDHAM, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and- State of Pennsylvania, have invented certain new and useful Improvements in Pneumatic Tools, of which the following is a specification.

Objects of the present invention are to firmly secure together the handle and the cylinder of the tool so that such disadvantageous features as were heretofore encountered by reason of the relative loosening of these parts may be obviated; to provide a tool that will work comparatively fast with the expenditure of relatively little effort for holding it; to provide a tool which will work satisfactorily, even with a comparatively loose valve; to obtain'the advantages incident to the use of larger straight air inlet and exhaust ports; to provide a tool which will strike a comparatively greater num-' vber of harder blows than heretofore and to cut down or reduce the vibrations of'the tool.v

To these and other ends hereinafter set forth the invention stated in general terms comprises the improvements to be presently described and finally claimed.

The nature, characteristic features and scope of the invention will be more fully understood from the following description taken in connection with the accompanying drawings forming part hereof and in which Figure 1, is a view principally in section of a tool embodying features of the invention. Fig. 2, is a sectional view drawn to an enlarged scale and illustrating the valve in positioncorresponding with the inward stroke of the plunger. Fig. 3, is a similar view with the valve in position corresponding to the outward stroke of the plunger. Fig. 4, is a face view of the complete valve block. Fig. 5, is a similar view with a portion of the valve block removed-to show the valve. Fig. 6, is a detached view illustrating in side elevation the two parts of the block, and the valve.

Fig. 7, lS a face view of the valve, and Fig. 8, is a sectional view illustrating a modification of the invention.

In the drawings 1, is the cylinder and 2 the handle.

' The socket of the latter is tapped as usual and split and provided with a bolt 3 by which it. can be contracted onto the threaded end of the cylinder 1. However, the cylinder is provided with a knurled collar or band 4 which is gripped by an unthreaded portion 5 of the socket. The effect of-interposing a knurl between the socket and cylinder-is that when the socket is clamped or contracted the knurl prevents accidental or undue motion of the handle in respect to the cylinder, which is obviously desirable. The handle is provided with a notch fitted with projections 6 so that a piece of flexible tube as rubber 7, maybe inserted in the notch with. the projection 6 entering its end, so as to hold it to place. The flexible tube 7 relieves the hand of the operator from the effects of vibration and at the same time Specification of Letters Patent.

'Applicstion filed April 21. 1904- Serial No. 204,177.

Patented Ju1y9, 1e07,. I

affords means for obtaining a firm grasp of the tool. The I handle is fitted with an air intake 8 which enters-it from the side and leaves it actually atthe base of the-- socket. Lengthwise of the handle and'transver'selyof the air intake is arranged a valve chamber 9 within whichis arranged a throttle valve 10 having a peripheral notch 11 cut in it.

12, is a spring which engages to shift the valve toward the left in the drawings.

a head on the valve 10 and a shoulder on the valve seat 9,so that it tends 13, is a push button havingits shankvand elon I.

gated slot in which works a pin 14,so that when the push button is pushed toward the-right it. shifts the valve 10 bringing the notch .or groove 11 into more or less perfect alinement with the air intake Sand 'thercby controlling and regulating the supplyoi Tho... handle is also provided with. openings as 15 for the escape of'exhaust air. Within the handle is mounted the valve block 16 which reallyconsists of two parts 16 and 16 WlllCl1.'2l.16 shown as fitted to gether by means of suitable dowel pinswhich serve 'to guide the complete valve, block in respect I to the cylinder 1. -Externallythe-valve block-is cylindrical and is providedwith agroove 17. In; i

-ternally there is a central opening through, thportion 16 which opening ieceives the valve 18 and is closed by the portion 16?. Internally the portion is provided with a cylindrical opening 119 of, comparatively large diameter and anopening 20 of com paratively small diameterso as to accommodate the large and small ends of the valve 18. 'The portion 20 is provided with a groove 21 and .r'r' channel 22. There is what 'may be called-a flip port 23 wliich' communicates with the groove 21 and extends" to the flip hole 24. There are exhaust ports 25 which coin-f municate with the largest portion of the opening in theblock and extend radially outward through'it. There are ports 26 which extend irom'the recess '22,

Inunicate with the interior of the cylinder There is also a port 2-7 whichcxtends fimtradially generally radially and then forwardly, soas' to' cqm-= I 1 serve both as admission and exhaust ports and then lengthwise through the wall of the cylinder} from the portion 19 to the opening 28 which coinmunib cates with the interior of the cylinder comparatively near the tool and it joins the portion 19 nearerto the tool than the exhaust ports 25. In the portion .16;

there is a portion 29 which extends from its face so communicate with the chamber 19 radially and tlien crosswise through it, so as tocommunicate with,a

passage 30 that communicates with the interior oflthe 5 cylinder at :51 and 32. Internally the valve18 is partially hollowed out at its small end and thisliollow portion communicates with radial openings 33 and there, is a port 34 within the valvewhiph com- 35 upon the exterior ol its larger end. In all positions of the valve 18 air under pressure reaches the flip hole 24 by way of the opening 23 because when the valve is in the position shown in Fig. 2, the openings 33 are in line with the groove 21 which communicates with the passage 23 and when the valve is in the positionsho wn in Fig. 3, the opening 23 is in direct communication with the groove 20 which is exposed to the incoming air. r

The cylinder 1 is internally provided with projecttions 36 and 37 and it is also provided with an air vent or opening 38. The piston 39 is grooved as at 40 and provided with an end as 41 of somewhat reduced diameter. Referring to Figs. 1 and2the piston 39 is moving toward the left. Air under pressure is present at the flip hole 24 and it reaches by way of the reduced portion 40 and opening 31 the passage 30 which leads lO the chambemadjacent the larger end of the valve, thus itis tending to hold the valve in the position shown. Air is also traversing theopening 34 in the valve, reaching its external gr'oove'35 and from thence .by way of the passage 27 is escaping at the opening 28,

thus operating upon the right-hand face adjacent the reduced portion 41 and so impellingthe piston toward the left. The openings 26 are in direct communication with the exhaust openings 25 by way of the reduced portion or neck 42 of the valve 18. The piston continues to movetoward the left until the reduced projection 41 comes opposite the opening 32 whereupon air escapes from thechamber adjacent the larger end of the valve 18 by way'oi the passage 30. At this time the portion 39 of the piston is opposite the flip hole 24 and closes it; Thus the valve 18 under the intluenceof air in the air intake 8 is shifted toward ,the right into the position shown in Fig. 3. The result of this is that the openings 33 in the valve 18 are brought. into line with the recess 22 which in its turn communicates directly with the openings 26 so that air rushes in an unobstructed manner throughthe openings 26 and drives the piston toward the right,

so as to strike the required blow. The vent or oped ing 38 serves to permit of the free escape of air without retarding the oncoming piston. Upon the completion of this stroke the groove 40 on the piston is again in alinement with the flip opening 24 and open ing 31, so that air under pressure by way of the passage 30 reaches the chamber adjacent the larger end of the valve and thus shifts the valve again into the position shown in Figs. 1. and 2 ready ior a repetition of the described operation. I

Obviously the air inlets and outlets for the passages 26 are comparatively unrestrictive and straight which is manifestly advantageous and since: the exhaust. ports 25 are located between the smaller and larger ends ol' 1h 0 valve it follows that even if the valve should be somewhat leaky any air that escaped past its small end would leave by the exhaust ports withour operating upon the larger face of the valve, so that the valve will remain balanced and operative even ii Hl1l('\\'ll1ll leaky.

Fig. 5 illustrates a modification of the invention, in

municates with its open interior and with a groove crosswise of the handle and consists of a valve proper 43 having upon its surface a groove 44. Air enters by way of the intake 45 and part of it reaches the chamber 46 by way of the port 47 and serves to tend to place the valve in the position shown. There is a pivotal handle 48 which operatesupon the end of the valve' and pushes it against the pressure of air in thechamber 46, so as to control the passage. of air through the openings 49 and 50 and groove It will be obvious to those skilled in the art to which my invention relates that modifications may be made in details without departing from the spirit thereof, hence I do not limit. myself to the precise mode of procedure or construction, but

Having thus described the nature and objects of my invention what I claim as new and desire to secure by Letters Patent is 1. The combination of a threaded cylinder, a threaded handle provided with tightening means, and a knurled band or collar interposed between the cylinder'and handle and adapted to be engaged by said tightening means, substantially as described. t 2. The combination of a handle provided with'a tapped split socket having clamping means, a threaded cylinder, and a knurled bandor collar interposed between the two, substantially as described.

3. The combination of a handle provided with a'split socket of which a portion is' tapped and which is provided with a clamping bolt and a cylinder provided with a threaded end and with a knurled collar which is engaged .by the socket, substantially as described.

" 4. In a pneumatic tool a handle provided with a recess "having projections, and a flexible tube arrangedin thev recess with the projections extending into its ends, substantially as described.

5. In a pneumatic tool the combination of a valve block internally provided with chambers of difierent sizes to accommodate the ditterential areas of the valve and with'a. groove and a recess, a port from the groove'for the flip opening, ports from the recess for admission and exhaust for striking the blow, ports from the larger internal opening througl'i the curved surface of the block for escape to the atmosphere, :1 port arranged in advance of the last mentioned ports for effecting the return of the piston, a port from .the front plate of the valve block to the larger internal chamber opening to conduct air for operating upon the larger: area of the valve, a piston and its cylin- .der,, a valve having a larger and smaller area and being hollow in rear of the larger area and having a contracted neck, radial openings through the smaller part of the valve and a groove on the larger part of the valve in communication with the whole interior thereof, substantially as described.

6. in apneumatic tool the combination of a valve blockhaving larger and smaller chambers for the accommodation of the ditterentiatareas of the valve, arecess in the smaller chamber, a set-of ports communicating with the recessand adapted to serve for admission and exhaust, a set of passages communicating with the larger chamber and with theatmosphere, a valve having differential areas connected by a neck and being hollow near the smaller area and provided with radial openings and provisions for shifting the valve whereby its openings are brought into alineinent with the admission and exhaust ports. to supply air for striking the blow and whereby its neck bridges the last mentioned ports and the passages which communicate whereof the larger one is closed and the smaller one is' open at the pressure end, exhaust ports, arranged in the wall of the larger chamber and admission ports arranged in the wall of the smaller chamber, and a valve consisting of a neck'provided at its extremities with a closed end and with a tubular laterally perforated end of uniform diameter arranged in the smaller chamber of the block, and cooperating with the admission ports, substantially as de-v scribed.

9. in a pneumatic tool the combination of a partly tubu-v lar valve consisting of a neck terminating in two heads whereof each is of substantially uniform diameter throughout its length and terminates in a substantially flat face or end'and whereof one is provided with anuannular groove connecting with the tubnlar part and whereof the' other contains the tubular part and coriati tntes a cut-0E for live air; with a valve block having means for admitting live air to thetubular part and conveying it from said groove and from the last mentioned head; and having provisions for conveying exhaust around and past the neck, substantially as described.

In testimony whereof I have hereunto signed my name.

. SAMUEL OLDHAM.

Witnesses W. .T. JACKSON, FRANK E. FRENCH. 

